Why retain Baltimore and Des Moines cruisers?

Why were some Baltimore and Des Moines class cruisers retained into the Cold War?

They supported shore operations and offered a smaller force for countering surface raiders than a carrier battle group.

The answer sees naval gunfire support as the primary reason to keep some Baltimore- and Des Moines-class heavy cruisers. Their large guns could support forces ashore in conflicts such as Vietnam without consuming missiles or carrier sorties. Anti-raider work supplied another role because a small cruiser detachment could pursue a Soviet Sverdlov-class threat in the Indian Ocean, South Atlantic, or South Pacific. Des Moines also retained enough armour to face the roughly 6-inch weapons carried by such opponents. That option prevented a remote surface raider from drawing an entire carrier battle group away from the Atlantic or Pacific main effort.